feat: ability to edit status messages (#1126)

* SetStatusMessage

* Docstring

* statusLine in header

* Use statusLine as []byte + ResponseHeader parsing

* status line getter

header.go

@@ -33,6 +33,7 @@ type ResponseHeader struct {
 	noDefaultDate        bool
 
 	statusCode            int
+	statusLine            []byte
 	contentLength         int
 	contentLengthBytes    []byte
 	secureErrorLogMessage bool
@@ -136,6 +137,19 @@ func (h *ResponseHeader) SetStatusCode(statusCode int) {
 	h.statusCode = statusCode
 }
 
+// StatusLine returns response status line.
+func (h *ResponseHeader) StatusLine() []byte {
+	if len(h.statusLine) > 0 {
+		return h.statusLine
+	}
+	return statusLine(h.StatusCode())
+}
+
+// SetStatusLine sets response status line bytes.
+func (h *ResponseHeader) SetStatusLine(statusLine []byte) {
+	h.statusLine = append(h.statusLine[:0], statusLine...)
+}
+
 // SetLastModified sets 'Last-Modified' header to the given value.
 func (h *ResponseHeader) SetLastModified(t time.Time) {
 	h.bufKV.value = AppendHTTPDate(h.bufKV.value[:0], t)
@@ -683,6 +697,7 @@ func (h *ResponseHeader) resetSkipNormalize() {
 	h.connectionClose = false
 
 	h.statusCode = 0
+	h.statusLine = h.statusLine[:0]
 	h.contentLength = 0
 	h.contentLengthBytes = h.contentLengthBytes[:0]
 
@@ -731,6 +746,7 @@ func (h *ResponseHeader) CopyTo(dst *ResponseHeader) {
 	dst.noDefaultDate = h.noDefaultDate
 
 	dst.statusCode = h.statusCode
+	dst.statusLine = append(dst.statusLine[:0], h.statusLine...)
 	dst.contentLength = h.contentLength
 	dst.contentLengthBytes = append(dst.contentLengthBytes, h.contentLengthBytes...)
 	dst.contentType = append(dst.contentType, h.contentType...)
@@ -1639,7 +1655,12 @@ func (h *ResponseHeader) AppendBytes(dst []byte) []byte {
 	if statusCode < 0 {
 		statusCode = StatusOK
 	}
-	dst = append(dst, statusLine(statusCode)...)
+
+	if len(h.statusLine) > 0 {
+		dst = append(dst, h.statusLine...)
+	} else {
+		dst = append(dst, statusLine(statusCode)...)
+	}
 
 	server := h.Server()
 	if len(server) != 0 {
@@ -1859,6 +1880,9 @@ func (h *ResponseHeader) parseFirstLine(buf []byte) (int, error) {
 		}
 		return 0, fmt.Errorf("unexpected char at the end of status code. Response %q", buf)
 	}
+	if len(b) > n+1 && !bytes.Equal(b[n+1:], statusLine(h.statusCode)) {
+		h.SetStatusLine(b[n+1:])
+	}
 
 	return len(buf) - len(bNext), nil
 }

header_test.go

@@ -36,7 +36,7 @@ func TestResponseHeaderAddContentType(t *testing.T) {
 func TestResponseHeaderMultiLineValue(t *testing.T) {
 	t.Parallel()
 
-	s := "HTTP/1.1 200 OK\r\n" +
+	s := "HTTP/1.1 200 SuperOK\r\n" +
 		"EmptyValue1:\r\n" +
 		"Content-Type: foo/bar;\r\n\tnewline;\r\n another/newline\r\n" +
 		"Foo: Bar\r\n" +
@@ -52,6 +52,10 @@ func TestResponseHeaderMultiLineValue(t *testing.T) {
 		t.Fatalf("parse response using net/http failed, %s", err)
 	}
 
+	if !bytes.Equal(header.StatusLine(), []byte("SuperOK")) {
+		t.Errorf("parse status line with non-default value failed, got: %s want: SuperOK", header.StatusLine())
+	}
+
 	for name, vals := range response.Header {
 		got := string(header.Peek(name))
 		want := vals[0]
@@ -78,6 +82,10 @@ func TestResponseHeaderMultiLineName(t *testing.T) {
 		})
 		t.Errorf("expected error, got %q (%v)", m, err)
 	}
+
+	if !bytes.Equal(header.StatusLine(), []byte("OK")) {
+		t.Errorf("expected default status line, got: %s", header.StatusLine())
+	}
 }
 
 func TestResponseHeaderMultiLinePaniced(t *testing.T) {

http_test.go

@@ -837,6 +837,24 @@ func TestResponseSkipBody(t *testing.T) {
 		t.Fatalf("unexpected content-type in response %q", s)
 	}
 
+	// set StatusNoContent with statusLine
+	r.Header.SetStatusCode(StatusNoContent)
+	r.Header.SetStatusLine([]byte("HTTP/1.1 204 NC\r\n"))
+	r.SetBodyString("foobar")
+	s = r.String()
+	if strings.Contains(s, "\r\n\r\nfoobar") {
+		t.Fatalf("unexpected non-zero body in response %q", s)
+	}
+	if strings.Contains(s, "Content-Length: ") {
+		t.Fatalf("unexpected content-length in response %q", s)
+	}
+	if strings.Contains(s, "Content-Type: ") {
+		t.Fatalf("unexpected content-type in response %q", s)
+	}
+	if !strings.HasPrefix(s, "HTTP/1.1 204 NC\r\n") {
+		t.Fatalf("expecting non-default status line in response %q", s)
+	}
+
 	// explicitly skip body
 	r.Header.SetStatusCode(StatusOK)
 	r.SkipBody = true